Type Ia supernovae are believed to be white dwarfs disrupted by a thermonuclear explosion. Here we investigate the scenario in which a rather low-mass, carbon-oxygen (C + O) white dwarf accumulates helium on its surface in a sufficient amount for igniting a detonation in the helium shell before the Chandrasekhar mass is reached. In principle, this can happen on white dwarfs accreting from a non...

This paper reports a numerical study on the effect of turbulence on the detonation wave properties. The analysis is based on the integration of the chemically reactive Navier– Stokes equations using a Runge–Kutta scheme and a fifth-order WENO spatial discretization. We perform a direct numerical simulation (DNS) of the fluid-mechanics equations in three dimensions to determine the fine-scale ev...

Developmental testing of high explosives for military applications involves small-scale formulation, safety testing, and finally detonation performance tests to verify theoretical calculations. small-scale For newly developed formulations, the process begins with small-scale mixes, thermal testing, and impact and friction sensitivity. Only then do subsequent larger scale formulations proceed to...

A simplified method is shown, based on a semi-empirical procedure, to estimate the detonation velocities of CHNO explosives at various loading densities. It is assumed that the product composition consists almost of CO, CO2, H2O and N2 for oxygen-rich explosives. In addition solid carbon and H2 are also counted for an oxygen-lean explosive. The approximate detonation temperature, as a second ne...

One of the basic equations to analyze the detonation of high explosives is the equation of state of the detonation products. Due to the very high pressure of the product, the direct measurement of the thermodynamic variables such as pressure or temperature is not possible. In this research, the parameters of BKW and HOM equations of state of detonation products are determined via experimental m...

This review presents a concept, which assumes that thermal decomposition processes play a major role in defining the sensitivity of organic energetic materials to detonation initiation. As a science and engineering community we are still far away from having a comprehensive molecular detonation initiation theory in a widely agreed upon form. However, recent advances in experimental and theoreti...

Here we analyze properties of an equation that we previously proposed to model the dynamics of unstable detonation waves [A. R. Kasimov, L. M. Faria, and R. R. Rosales, Model for shock wave chaos, Phys. Rev. Lett., 110 (2013), 104104]. The equation is ut+ 1 2 ( u2 − uu 0−, t x = f ( x, u ( 0−, t )) , x ≤ 0, t > 0. It describes a detonation shock at x = 0 with the reaction zone in x < 0. We inve...

D ETONATION, a shock-induced combustion process in which the heat releasemakes a strong contribution to the support of the lead shock, is one of the most rapid chemical energy release processes in nature. For self-sustained detonations propagating in gases initially at atmospheric pressure and temperature, energy release rates approaching 10 W=m are not uncommon, and propagation velocities on t...

4 simplified model that can predict the transition from compaction to detonation and shock to detonation is given with the uim of describing experiments in beds of porous HMX. In the case of compaction to detonation. the energy of early impact generates a slowly moving. convectivereactive deflagration that expands near the piston face and evolves in a manner that is characteristic of confined d...

Detonation Shock Dynamics (DSD) is a detonation propagation methodology that replaces the detonation shock and reaction zone with a surface that evolves according to a specified normal-velocity evolution law. DSD is able to model detonation propagation when supplied with two components: the normaldetonation-velocity variation versus detonation surface curvature and the surface edge angle at the...